They are only children of not more than twelve and don’t realizeto organize such an exhibi

问题补充：

They are only children of not more than twelve and don’t realizeto organize such an exhibition.

A. when they take

B. what it takes

C. how they take

D. what takes them

答案：

A. when they take

(答案→)B. what it takes

C. how they take

D. what takes them

解析：这是宾语从句，宾语从句中take 缺少宾语，所以用what。